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  • 1
    Electronic Resource
    Electronic Resource
    ELECTROMAGNETIC FIELDS: Human Safety Issues (2002)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Biomedical Engineering 4 (2002), S. 211-234 
    Details
    ISSN: 1523-9829
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Technology , Medicine
    Notes: Abstract Most of the recently revised safety standards worldwide are set in terms of internal rates of electromagnetic energy deposition (specific absorption rates or SAR) at radio frequencies (RF) and microwave frequencies, and of induced electric fields or current densities at lower frequencies up to 10 MHz. Numerical methods have been developed that use millimeter resolution anatomically based models of the human body to determine SAR or the induced electric fields and current densities for real-life EM exposure conditions. A popular method for use at RF and microwave frequencies is the finite-difference time-domain method. This method is described and illustrated for SAR distributions due to cellular telephones for head models based on human anatomy. A method often used for calculations of induced electric fields and current densities at low frequencies is the impedance method. Use of this method is illustrated by an example of an electronic article surveillance (EAS) system for anatomic models of an adult and 10- and 5-year-old children. Experimental phantoms using a fluid to simulate the dielectric properties of the brain may be used for determination of peak 1- or 10-g SAR needed for compliance with the various safety standards.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.bioeng.4.020702.153447
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  • 2
    Electronic Resource
    Electronic Resource
    Raman spectroscopy of liposomes exposed to millimeter waves (1986)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 60 (1986), S. 2991-2994 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Several biological effects resulting from exposure to millimeter waves have been reported. In an attempt to determine if millimeter waves might affect the conformational state of membranes, sonicated liposomes have been irradiated with millimeter waves at 41.650 GHz, stabilized in frequency to ±50 Hz. Raman spectra from the lipid vesicles were then collected in the conformational and in the C-H stretching region. No changes in either the Raman peak locations or relative intensities were detected upon millimeter-wave irradiation, either below or above the transition temperature of the phospholipid (41 °C).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.337752
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  • 3
    Electronic Resource
    Electronic Resource
    Behavioral effects of chronic exposure to 0.5 mW/cm2 of 2,450-MHz microwaves (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 8 (1987), S. 149-157 
    Details
    ISSN: 0197-8462
    Keywords: microwave ; behavior ; rat ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Adult male, Long-Evans rats were exposed 7 h a day for 90 days to continuous wave (CW) 2,450-MHz microwaves at an average power density of 0.5 mW/cm2. Exposures were in a monopole-above-ground radiation chamber with rats in Plexiglas cages. The resulting specific absorption rate (SAR) was 0.14 W/kg (±0.01 SEM). Additional rats served as sham-exposed and home-caged controls. All were evaluated daily for body mass and food and water intakes. Once each 30 days, throughout baseline and exposure phases of the experiment, rats in the sham- and microwave-exposed groups were tested for their sensitivity to footshock. After 90-days of exposure, the rats were evaluated an open field, an active avoidance task and an operant task for food reinforcement. Performance of sham-and microwave-irradiated rats was reliably different on only one measure, the lever-pressing task. The general conclusion reached was that exposure to CW 2,450-MHz microwave radiation at 0.5 mW/cm2 was below the threshold for behavioral effects over a wide range of variables, but did have an effect on a time-related operant task, although the direction of the effect was unpredictable.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250080205
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  • 4
    Electronic Resource
    Electronic Resource
    Carl H. Durney. 1993 recipient of the d'Arsonval medal (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 15 (1994), S. 3-4 
    Details
    ISSN: 0197-8462
    Keywords: Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250150105
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  • 5
    Electronic Resource
    Electronic Resource
    Absorption of microwave radiation by the anesthetized rat: Electromagnetic and thermal hotspots in body and tail (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 8 (1987), S. 385-396 
    Details
    ISSN: 0197-8462
    Keywords: SAR ; blood flow ; temperature ; frequency ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Anatomic variability in the deposition of radiofrequency electromagnetic energy in mammals has been well documented. A recent study [D'Andrea et al., 1985] reported specific absorption rate (SAR) hotspots in the brain, rectum and tail of rat carcasses exposed to 360- and to 2,450-MHz microwave radiation. Regions of intense energy absorption are generally thought to be of little consequence when predicting thermal effects of microwave irradiation because it is presumed that heat transfer via the circulatory system promptly redistributes localized heat to equilibrate tissue temperature within the body. Experiments on anesthetized, male Long-Evans rats (200-260 g) irradiated for 10 or 16 min with 2,450, 700, or 360 MHz radiation at SARs of 2 W/kg, 6 W/kg, or 10 W/ kg indicated that postirradiation localized temperatures in regions previously shown to exhibit high SARs were appreciably above temperatures at body sites with lower SARs. The postirradiation temperatures in the rectum and tail were significantly higher in rats irradiated at 360 MHz and higher in the tail at 2,450 MHz than temperatures resulting from exposure to 700 MHz. This effect was found for whole-body-averaged SARs as low as 6 W/kg at 360 MHz and 10 W/kg at 2,450 MHz. In contrast, brain temperatures in the anesthetized rats were not different from those measured in the rest of the body following microwave exposure.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250080407
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  • 6
    Electronic Resource
    Electronic Resource
    Intermittent exposure of rats to 2450 MHz microwaves at 2.5 mW cm2: Behavioral and physiological effects (1986)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 7 (1986), S. 315-328 
    Details
    ISSN: 0197-8462
    Keywords: microwave exposure ; behavior ; physiology ; pathology ; blood chemistry ; neurobehavioral toxicology ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Long-Evans male adult rats were intermittently exposed for 14 weeks to continuous wave (CW) 2450-MHz microwaves at an average power density of 2.5 mW/cm2. The mean specific absorption rate was 0.70 W/kg (± 0.02 SEM). The rats were exposed 7 h/day, 7 days/week in a radiation chamber with a monopole above ground, while housed in Plexiglas cages. Weekly measures of body mass and food intake did not indicate statistically significant effects of microwave irradiation. Assessments of threshold for electric-footshock detection revealed a significant difference between microwave and sham-exposed animals. Assessments of cholinesterase and sulfhydryl groups in blood and 17-ketosteriods in urine did not distinguish the two groups of rats. Behavioral measures made at the end of the 14-week exposure included an open-field test, shuttlebox avoidance performance, and schedule-controlled lever-pressing for food pellets. Statistically significant differences between microwave- and sham-exposed rats were observed for these measures. Examination of adrenal tissue, plasma electrolytes, and organ masses after 14 weeks of exposure revealed no difference between the two groups of rats.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250070308
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  • 7
    Electronic Resource
    Electronic Resource
    Currents induced in a model of a rat exposed to EMP in a parallel-plate line: Calculations and experimental results (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 13 (1992), S. 439-443 
    Details
    ISSN: 0197-8462
    Keywords: Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250130511
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  • 8
    Electronic Resource
    Electronic Resource
    Numerical dosimetry at power-line frequencies using anatomically based models (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 13 (1992), S. 43-60 
    Details
    ISSN: 0197-8462
    Keywords: scaled frequency FDTD method ; induced current densities ; pure electric or magnetic fields ; combined electric and magnetic fields ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: We have used the finite-difference time-domain (FDTD) method to calculate induced current densities in a 1.31-cm (nominal 1/2 in) resolution anatomically based model of the human body for exposure to purely electric, purely magnetic, and combined electric and magnetic fields at 60 Hz. This model based on anatomic sectional diagrams consists of 45,024 cubic cells of dimension 1.31 cm for which the volume-averaged tissue properties are prescribed. It is recognized that the conductivities of several tissues (skeletal muscle, bone, etc.) are highly anisotropic for power-line frequencies. This has, however, been neglected in the first instance and will be included in future calculations. Because of the quasi-static nature of coupling at the power-line frequencies, a higher quasi-static frequency f′ may be used for irradiation of the model, and the internal fields E′ thus calculated can be scaled back to the frequency of interest, e.g., 60 Hz. Since in the FDTD method one needs to calculate in the time domain until convergence is obtained (typically 3-4 time periods), this frequency scaling to 5-10 MHz for f′ reduces the needed number of iterations by over 5 orders of magnitude. The data calculated for the induced current and its variation as a function of height are in excellent agreement with the data published in the literature. The average current densities calculated for the various sections of the body for the magnetic field component (H) are considerably smaller (by a factor of 20-50) than those due to the vertically polarized electric field component when the ratio E/H is 377 ohms. We have also used the previously described impedance method to calculate the induced current densities for the anatomically based model of the human body for the various orientations of the time-varying magnetic fields, namely from side to side, front to back, or from top to bottom of the model, respectively. 1992 Wiley-Liss, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250130706
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  • 9
    Electronic Resource
    Electronic Resource
    Microwave radiation absorption in the rat: Frequency-dependent SAR distribution in body and tail (1985)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 6 (1985), S. 199-206 
    Details
    ISSN: 0197-8462
    Keywords: microwave ; SAR ; hotspots ; dose distribution ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Experiments were conducted using twin-well calorimetry to determine the averaged whole-body specific absorption rate (SAR) for rat carcasses exposed to 360, 700, 915, and 2,450 MHz CW radiation in an anechoic chamber. All exposures were done with the long axis of the rat in an E-polarization. Additional experiments were conducted using a fiber optical temperature probe to determine local SAR in the brain, esophagus, colon, rectum, and tail during microwave exposure. The whole-body averaged SAR for the radiation frequencies examined follows a nonmonotonic function with 700 MHz as the resonant frequency. This result agrees with previous analytical estimates. Local SARs within the body and tail are nonuniform with significant frequency-specific hotspots in the colon, rectum, and tail.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250060211
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  • 10
    Electronic Resource
    Electronic Resource
    Behavioral and physiological effects of chronic 2,450-MHz microwave irradiation of the rat at 0.5 mW/cm2 (1986)
    New York, NY [u.a.] : Wiley-Blackwell
    Bioelectromagnetics 7 (1986), S. 45-56 
    Details
    ISSN: 0197-8462
    Keywords: microwaves ; rats ; behavior ; Life and Medical Sciences ; Occupational Health and Environmental Toxicology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Adult male Long-Evans rats were intermittently exposed to 2450 MHz CW microwaves at an average power density of 0.5 mW/cm2 for 90 days. The resulting SAR was 0.14 W/kg (range 0.11 to 0.18 W/kg). The animals were exposed 7 h/day, 7 days/wk, for a total of 630 h in a monopole-above-ground radiation chamber while housed in Plexiglas holding cages. Daily measures of body mass and food and water intake indicated no statistically significant effects of microwave exposure. Monthly assessment of reactivity to electric footshock, levels of cholinesterase and sulfhydryl groups in blood, and 17-ketosteroids in urine revealed no reliable differences between 14 sham-exposed and 14 microwave-exposed rats. After the 90 days of exposure, seven rats, randomly chosen from each group, were assessed for open-field behavior, shuttlebox performance, and schedule-controlled (IRT schedule) lever pressing for food pellets. Statistically significant differences between microwave-exposed and sham-exposed rats were observed in shuttlebox performances and lever pressing. Post mortem measures of mass of several organs and microscopic examination of adrenal tissue revealed no differences between the two groups of animals.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bem.2250070106
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